How to Propagate Rose of Sharon? Detailed Guide to Seed Sowing and Cutting Methods

Rose of Sharon (Hibiscus syriacus) has strong adaptability and is cultivated in both northern and southern China, but it has poor cold tolerance, so protection against cold should be taken during freezing weather. Generally, Rose of Sharon can be propagated by two methods: seed sowing and cuttings. Here is a detailed introduction to these two propagation methods.

Rose of Sharon

I. Seed Propagation

Generally carried out in April in spring. After the fruit matures in October, the best time to collect seeds is from November to December. After harvesting, extract the seeds and store them dry at low temperature. By the following spring in April, sow them in drills or broadcast. For division propagation, after leaf fall in autumn or before bud break in early spring, dig up the suckers growing from the root zone of the plant and replant them separately. Before planting, the roots can be trimmed appropriately, and the above-ground parts should be heavily cut back. Rose of Sharon has strong adaptability, is easy to cultivate, and requires minimal management, generally allowing it to grow freely. However, to improve its ornamental effect and make its flowers abundant and colorful, necessary management should be provided. Rose of Sharon blooms on new growth of the current year, and appropriate pruning can be done after leaf fall in autumn. When pruning, thinning should be combined with heading back; long branches should be moderately cut back, and overly dense branches and weak thin branches should be thinned out to concentrate nutrients and make the plant full. In mid-to-late April after the plant sprouts in spring, apply fertilizer once and water promptly to ensure sufficient fertilizer and water in the soil. When planting Rose of Sharon, apply base fertilizer in the planting hole, and generally no further fertilization is needed afterward. From before bud break in spring to the flowering period in summer, irrigate 2 to 3 times depending on the weather. Drain water to prevent waterlogging during the rainy season. After autumn and before frost, irrigate once thoroughly to prevent freezing. Do not irrigate in late summer and early autumn, to avoid autumn shoots growing too tender and reducing cold resistance. For seedlings under 5 to 6 years old, cold protection measures such as mounding soil around the roots should be taken when overwintering.

II. Cutting Propagation

Rose of Sharon has a high survival rate with cuttings, and cutting material is relatively easy to obtain, so cutting propagation is commonly used. Cutting propagation should be carried out in early spring before branches and leaves sprout. Select healthy, pest-free and disease-free plants as mother plants. Before the mother plant sprouts, select 1-to-2-year-old middle and upper branches with a diameter of more than 1 cm as propagation material. Cut the branches into 15-to-20-cm segments, soak in clean water for 4 to 6 hours, then insert the cuttings. Before cutting, prepare the seedbed well. Make beds with a bed-and-furrow width of 130 cm and a height of 25 cm. Apply 6 kg of barnyard manure, 1.5 kg of burnt soil, and 75 g of calcium magnesium phosphate per square meter as base fertilizer. For cutting, require a furrow depth of 15 cm, a furrow spacing of 20 to 30 cm, and a plant spacing of 8 to 10 cm. The upper end of the cutting should be exposed 3 to 5 cm above the soil surface, or the insertion depth should be 2/3 of the cutting. After inserting, firm the soil and water promptly. Cuttings generally take about 1 month to root and sprout. Using plastic greenhouses or other insulation and warming facilities, cutting propagation can also be carried out after leaf fall in autumn. Soak the prepared cuttings in a 100-to-200 mg/L NAA solution for 18 to 24 hours, water promptly, cover with agricultural film, maintain a temperature of 18 to 25°C and a relative humidity above 85%. After rooting, move them to the nursery for cultivation.

Since Rose of Sharon roots very easily from cuttings, when the number of plants to be cultivated is small, direct planting can be done by inserting the cuttings directly into planting holes at the cultivation density without the need for transplanting. Long branches can also be used for direct planting, which requires inserting them more than 20 cm deep into the soil to prevent lodging and drought damage caused by roots being too shallow.

How to Propagate Rose of Sharon: 4 Propagation Methods for Rose of Sharon

Cutting time: Can be done from mid-March to early April in combination with pruning and shaping.

Select 1-to-2-year-old healthy branches that have not yet sprouted, cut them into small segments 15 to 20 cm long, and insert them outdoors in red soil or sandy soil. The soil must be kept moist, but the survival rate is relatively low. It is best to insert them in a seedbed covered with plastic film to retain moisture, at a temperature of 17°C to 20°C, where they root very easily.

The sowing time is generally in April in spring. After the fruit matures in October, the best time to collect seeds is from November to December. After harvesting, extract the seeds and store them dry at low temperature. By the following spring in April, sow them in drills or broadcast.

Since Rose of Sharon branches root very easily, before sprouting in spring, dig a shallow furrow beside the mother plant, lay 1-year-old branches horizontally into the shallow furrow, cover with soil, and keep the soil in the layering furrow moist. They will root and send out shoots quickly. After leaf fall in autumn, cut the layered branches from the base, then dig out the seedlings and divide them into individual plants.

Division propagation is generally carried out before sprouting in early spring. Dig up vigorous mature clumps, take 3 main branches as 1 clump, and plant at a plant and row spacing of 50×60 cm.

Cultivation Techniques of Rose of Sharon: Propagation Methods of Rose of Sharon

Rose of Sharon is a common garden shrub flower, also known as white hibiscus, palm tree flower, big bowl flower, hedge flower, etc. It is a deciduous shrub or small tree of the genus Hibiscus in the mallow family. With brilliant colors, it is suitable for planting along roadsides, in parks, courtyards, and other places, and can be planted singly, in rows, or in groups. It grows relatively fast and has luxuriant branches and leaves. Let's take a look at the cultivation techniques of Rose of Sharon below!

Growth Habits of Rose of Sharon

Rose of Sharon is mainly distributed in tropical and subtropical regions, originating from the African continent. The Hibiscus genus in Africa has a great variety of species, showing rich genetic diversity. It has strong adaptability to the environment, is relatively tolerant of drought and poor soil, and has no strict requirements for soil. It especially prefers light and a warm, humid climate. It is slightly shade-tolerant, prefers a warm and humid climate, tolerates pruning, heat, and cold, but in northern regions it needs protection to overwinter. It likes moisture but is also drought-tolerant, has no strict requirements for soil, and can even grow in heavy clay. It has strong sprouting ability.

Cultivation Value of Rose of Sharon

1. Landscaping: Rose of Sharon is an important flowering shrub for summer and autumn. In the south, it is mostly used as a flower hedge or green hedge, while in the north it is used as a courtyard accent and indoor potted plant. Rose of Sharon has strong resistance to harmful gases such as sulfur dioxide and chlorides, and also has a strong dust-retention function, making it a main greening tree species for polluted factories.

2. Edible: Rose of Sharon has extremely high nutritional value, containing protein, fat, crude fiber, as well as reducing sugars, vitamin C, amino acids, iron, calcium, zinc, etc., and also contains flavonoid active compounds. The flower buds have a crisp texture when eaten, and fully bloomed Rose of Sharon flowers are smooth and refreshing when eaten. Rose of Sharon juice made from the flowers has a health benefits of quenching thirst and refreshing the mind. Patients with hypertension who regularly eat plain Rose of Sharon soup dishes experience good dietary therapeutic effects.

3. Medicinal: The flowers, fruits, roots, leaves, and bark of Rose of Sharon can all be used as medicine. They have the effect of preventing and treating viral diseases and lowering cholesterol. The flowers contain saponarin, isovitexin, saponins, etc., and have a certain inhibitory effect on Staphylococcus aureus and Salmonella typhi. They can treat intestinal wind and diarrhea; taken internally, they treat nausea, dysentery, rectal prolapse, hematemesis, bloody stool, mumps, excessive vaginal discharge, etc.; applied externally, they can treat sores, boils, and swellings.

Propagation Methods of Rose of Sharon

1. Division: For Rose of Sharon, division is done before sprouting in early spring. Dig up vigorous mature clumps, take 3 main branches as 1 clump, and plant at a plant and row spacing of 50×60 cm.

2. Cuttings: Rose of Sharon cuttings can be done from mid-March to early April in combination with pruning and shaping. Insert them outdoors in red soil or sandy soil, keep the soil moist, and at a temperature of 17°C to 20°C they root very easily.

3. Sowing: Seed propagation of Rose of Sharon is generally carried out in April in spring. After the fruit matures in October, the best time to collect seeds is from November to December. After harvesting, extract the seeds and store them dry at low temperature. By the following spring in April, sow them in drills or broadcast.

4. Layering: Rose of Sharon branches root very easily. Before sprouting in spring, dig a shallow furrow beside the mother plant, lay 1-year-old branches horizontally into the shallow furrow, cover with soil, and keep the soil in the layering furrow moist. They will root and send out shoots quickly.

Cultivation Techniques of Rose of Sharon

1. Transplanting: Rose of Sharon can be transplanted in both spring and autumn. Bare roots can be dipped in mud slurry, and some branch tips should be appropriately cut off. It survives very easily. When planting, apply base fertilizer in the planting hole, generally using compost or decomposed barnyard manure mixed with a small amount of compound fertilizer, and no further fertilization may be needed afterward.

2. Fertilizing: During cultivation of Rose of Sharon, in order to improve flower yield and quality, topdressing should be applied to weaker trees before flowering in summer. Compost mixed with an appropriate amount of compound fertilizer can be used and applied at the base in combination with weeding and hilling.

3. Watering: During cultivation of Rose of Sharon, pay attention to drainage to prevent waterlogging during the rainy season. During the flowering period, irrigate if there is drought. At the end of autumn, cut off late autumn shoots, overly dense branches, weak small branches, and dead branches to facilitate ventilation and light penetration, maintain plant shape, and protect against cold for overwintering.

4. Pruning: Rose of Sharon planted as hedges and walls should be shaped and pruned 2 to 3 times before spring sprouting and during the growing period. For those scattered in gardens, cut back the trunk in the spring of the second year after planting to promote branching at the base, so that 2-year-old seedlings can be trained into an ideal tree shape.

5. Hilling: During the growing period of Rose of Sharon, carry out weeding and hilling 2 to 3 times. Carry out the first hilling before seedlings sprout in spring, and carry out the second hilling in combination with weeding when branches have grown their 4th to 5th leaves after leaf expansion.

6. Pests: The main pests of Rose of Sharon include red spiders, aphids, bagworms, noctuid moths, longhorn beetles, etc. When pests and diseases occur, cut off diseased and pest-infested branches, and choose safe, efficient, low-toxicity pesticides for spray control or trapping. Attention should be paid to early control, and avoid applying pesticides during the flowering and harvest period to ensure that the harvested Rose of Sharon flowers are not contaminated by pesticides.

7. Diseases: Rose of Sharon commonly suffers from leaf spot disease and rust disease. Spray with a 600-fold dilution of 65% zineb wettable powder. Pests also include whiteflies and scarab beetles, mainly aphids, as well as inchworms and leaf roller moths, which can be controlled by spraying with a 1000-fold dilution of 40% omethoate emulsifiable concentrate. An environmentally safe insecticide method is to use diluted detergent.